The bay is known for hosting the world's largest tidal bore, being up to 9 metres (30&nbsp;ft) high, and travelling up to 40&nbsp;km (25&nbsp;miles) per hour. The tidal bore is especially high during the Mid-Autumn Festival when several thousand tourists come to watch the magnificent Qiantang Tidal Bore.

The bay is spanned by the Hangzhou Bay Bridge, which was linked up on June 14, 2007 and opened on 1 May, 2008. The second-longest bridge in the world, it cuts the trip between eastern Zhejiang and Shanghai from 400 to 80 kilometres (250 to 50 miles).